Bright or saturated colors draw immediate attention, but only if used in
limited amounts. They are useful for error messages, annotations, urgent commands, and, when simultaneously emphasized by a font change or special placement, key words. Used together, saturated colors (especially saturated complements) are extremely fatiguing, causing the eye to constantly refocus. The effect produces after-images. Except for unusual circumstances where visual vibration may be desired, combinations of bright or saturated colors should be avoided.